An integrated coal gasification combined cycle (hereinafter, referred to as “IGCC”) is a power generation system aiming at higher efficiency and higher environmental performance than a conventional coal-fired power generation, by gasifying coal in combination with C/C (combined-cycle power generation).
Although the IGCC has a great advantage in its ability to use coal, which is an abundant resource, it is known that the advantage is further enhanced by expanding the types of coal to be used.
For example, the IGCC that employs a dry coal feed system can even use coal with a relatively high moisture content, but a high moisture content carried by low-grade coal such as brown coal and sub-bituminous coal causes a reduction in power generation efficiency.
In order to solve this problem, a technology for drying coal by using high-temperature gasified gas, a technology for pulverizing coal by using gas-turbine exhaust gas, and a technology for drying coal by using gas-turbine exhaust gas are known (for example, see Patent Citations 1 and 2).
Patent Citation 1:    Japanese Unexamined Patent Application, Publication No. 2002-155288
Patent Citation 2:    Japanese Translation of PCT International Application, Publication No. Hei-08-500850